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// Example of a circular Tree
// Circular Trees are interesting in online real time environments
// to store the results of the last maxEntries events.
// for more info, see TTree::SetCircular
// Author: Rene Brun
void circular() {
gROOT->cd(); //make sure that the Tree is memory resident
TTree *T = new TTree("T","test circular buffers");
TRandom r;
Float_t px,py,pz;
Double_t random;
UShort_t i;
T->Branch("px",&px,"px/F");
T->Branch("py",&py,"px/F");
T->Branch("pz",&pz,"px/F");
T->Branch("random",&random,"random/D");
T->Branch("i",&i,"i/s");
T->SetCircular(20000); //keep a maximum of 20000 entries in memory
for (i = 0; i < 65000; i++) {
r.Rannor(px,py);
pz = px*px + py*py;
random = r.Rndm();
T->Fill();
}
T->Print();
}
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